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able covered building, and consists of one, two, or more shallow tray-like baths a connected at their ends with a common bath a l , with which communicates a conveyor or bucket-belt of. In the baths a are rakes or harrows b, preferably suspended by flexible connections c, such connections (which may be cords, chains, or the like) passing over pulleys and down to winches or other mechanism d, by which the harrows may be raised or lowered to suit the amount or quality of material in the bath, such harrows being preferably always suspended, so that they do not touch the bottom, and capable of being raised when required to empty the bath. A reciprocating movement is given to the harrows by means of the pitmen c, connected to the cranks of a shaft /, which is suitably rotated from a shaft f l , driven by a pulley f'\ from a pulley f 3 , on a main shaft f i , driven by suitable engines or motors. At the ends of the baths a are situated a, series of similar shallow tray-like baths g of larger dimensions, provided also with harrows or rakes h, hung on flexible connections c l , attached to winches d l , such rakes being operated by pitmen * connected to cranks on the shaft /*. These baths are preferably placed at a slight incline towards one end, where there are situated overflowchutes j j l , which overhang respectively the end tanks of a series of settling-tanks k, k l , k 2 . These tanks are each provided with pipes I, draining into a pipe common to all such pipes I, having cocks at different heights placed in the tanks, and communicating therewith. The tanks have also sloping bottoms, indicated at m, Fig. 3, communicating with doors m l , while between each pair of tanks k k or k 1 k 1 is a sump or pit, in which works an endless conveyor or bucket-belt n n l , arranged to deliver into troughs or launders oo 1 having each two spouts or branches passing to the tanks k 1 k 1 and ft 2 W respectively. Such spouts are provided with dams or doors p, as are also the chutes jj l and baths a a l . There are provided also suitable tanks qq and r for the mixing and storage of the cyanide or other dissolving working solutions. The teeth s of the rakes or harrows may be solid or hollow throughout their length, and open at their ends, as shown in Fig. 5, or they may be perforated, as at s l , Fig. 6, such teeth being connected through pipes with a flexible tube t, by which air, liquid, or gases may be forced or introduced into the body or mass of material in the baths. In carrying out the process the tailings, slimes, pulp from the mill, sands, alluvial or other matter to be treated, and in a more or less finely divided state, is elevated by the conveyor a? into the bath a l , supplied with water, and from thence overflows into the baths a, where it is subjected to a raking action in the water by the harrows. In these baths a any free gold present has an opportunity to settle. If clean and free-milling ores are being treated quicksilver may be placed in the bath to amalgamate the gold. The rest of the pulp is allowed to gradually flow over the ends or edges of the baths into the first bath or vat g, in which the pulp or tailings are treated with cyanide, bromine, chlorine, or other desired solutions, and which are continuously supplied to same. These baths are so arranged or inclined that the pulp and solution flow over the edge of the first one into the one next in order, the agitation to which they are subjected, and the large surface which is exposed by reason of the formation of the baths, enabling the pulp with cyanide or like solution to be brought very effectively into contact with the air. In these baths the fine gold is dissolved, and from them the tailings and solution flow by the chutes j or f into the tanks k k, where in due course the gold-bearing solution is drawn off by the pipes I and taken to the usual extractor-boxes, where it is treated in the ordinary way. The tailings remain at the bottom of the tank k until the door m 1 is opened, when it is discharged into the sump, in which works the conveyor n, which will raise the tailings and deliver it into the launder o, and from thence into the next tanks k 1 k l . This launder o may have a studded or ribbed bottom to break up the material, and will have a weak cyanide or like solution or water wash supplied to it. In the first tank the tailings may be deprived of, say, 50 per cent, of its bullion, and in the second tank, which also contains a cyanide or like solution, it will be deprived of, say, 50 per cent., or onehalf of the bullion remaining therein, after which the same process may be repeated, the tailings .being removed and elevated to the third tanks k 2, k 2 , and so on, as required to obtain as far as possible all the bullion contained therein, any suitable number or arrangement of tanks being employed, about one-half of the remaining bullion in the tailings being extracted at each operation. The tanks may be so arranged that one set are being used for settling while another set are being emptied of solution and tailings, as previously described, this being effected by the dams or doors p. By the means above described the coarse as well as the greater portion of the fine gold may be obtained within a few hours of crushing, the remainder being afterwards secured. The water required is considerably less than that used in battery treating, and the loss but little more than the moisture in the residues. The quantity required in the agitation can be as low as equal weight of tailings or slimes, while the strength of the solution will vary with the ore, but, for example, 0-01 per cent, will work with some slimes. In treating slimes direct and tailings carrying very fine gold, they may be delivered into the large baths g without the intervention of the first bath a. All free-milling ores, sands, and tailings may be leached as formerly, after the agitation as above described, wherever suitable. Where it is desired to use chlorine gas or the like under pressure, the baths g may be provided with gastight covers, and have suitable packing-boxes through which the parts operating the agitating-harrows work. By this process amalgamation by copper-plates and leaching of the cyanide or other solution is no longer necessary, nor is the presence of slimes to be feared, as the ore may be crushed dry or wet as fine as is possible in order to liberate the whole of the precious metal from the gangue. A small quantity of lime may be crushed with the ore or mixed in the first or concentrating baths a, for the double purpose of neutralising the acids in the ores and for causing a quick precipitation of the solid matter in the settling-tanks. In order to remove the soluble sulphates, acids, salts, and the like, a preliminary water wash may be necessary.